package example01;

public class Circle {
    private double r;//半径

//    public double getR() {
//        return r;
//    }

    //数据传递
    public void setR(double r) {
        //10是死数据
        System.out.println(r);
        this.r = r;
    }

    public double findArea(){
        double s = 3.14 * r * r;
        return s;
    }

}
